Health warning for Lake Ngangana in Waitara

20 September 2023

A health warning has been issued today for Lake Ngangana in Waitara.

The health warning is based on water test results and visual observations provided by the Taranaki Regional Council which indicate a dense bloom of potentially toxic blue-green algae.

Any activity which results in contact with the lake water should be avoided, says Dr Neil de Wet, Te Whatu Ora Medical Officer of Health for Taranaki.
“Contact with water affected by blue-green algae blooms can cause asthma and hay fever attacks in some individuals,” says Dr de Wet.

“Contact with the blue-green algae can also cause skin rashes, stomach upsets, and in some cases neurological effects such as tingling around the mouth, headaches, breathing difficulties and visual problems.

“Algal mats and scum may accumulate along the shoreline of the lake and so it’s especially important that parents ensure that children avoid contact with these as they may be toxic.”

Dogs are particularly at risk and should also be kept away from the shoreline. Elsewhere in New Zealand there have been reported deaths of dogs that have eaten toxic algae on shorelines.

Dr de Wet advises that it’s always a good idea to keep an eye out for signs of algal blooms if using lakes in our region and report any concerns to your local council.

“Algal blooms can develop rapidly and unpredictably and can sometimes produce toxins that are harmful for people as well as animals. If the water looks discoloured, has an unusual smell, or has green or brown particles floating in it then it is best to avoid contact with it.”

Signage has been erected at Lake Ngangana advising potential lake users about the algal bloom.

More information can be found on these webpages: 
Can I swim? (

Algae and Cyanobacteria in Lakes:

Last updated: Friday, September 1, 2023

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